Circuit controlling device



A118- 30, 1938- H. 1 MEKELBURG 2,128,373

CIRCUIT CONTROLLING DEVICE Aug. 30, 1938.` H. L. MEkx-:LBURG 3 CIRCUIT CONTROLLING DEVICE Filed Feb. 18, 1937 2 Sheets-Sheet 2 l @Mv/MMX @MM Patented Auhg. 30, 1938 omcm'r coN'rRoLLlNG DEVICE Harold L. Mekelburg, Milwaukee, Wis., asslgnor l to Cutler-Hammer, Inc., Milwaukee, Wis.,y a corf poration of Delaware Application February 18, 1937, Serial No. 126,367

10 Claims.

This invention relates to'circuit controlling devices; and while not limited theretois particularly applicable to multi-pole reversing switches for'electric motors. The invention has among its objects to provide an exceedingly compact and rugged control switch consisting of parts which can be economi- A cally manufactured and readily assembled.

Another object is to provide a control switch having cooperating stationary and movable contact elements of novel form.

Another object is to provide a. control switch 'Y of the aforesaid character in which the stationary and movable contact elements are made up almost entirely of molded 4insulating parts v illustrated is susceptible of modification without departing from the spirit and scope of the appended claims.

In the drawings,

Figure 1 is a side elevational view of a control switch embodying the invention, parts of the switch being shown in section;

Fig. 2 is a'front elevational view of the control switch shown in Fig. 1, a cover associated with the enclosing casing for the switch being removed; f

Figs. 3 and 4 are sectional views on lines 3-3 of Fig. 1 illustrating the switchin ofi position and in one of its on positions;

` Figs. 5, 6 and 7 are perspective views of certain of the parts shown in Figs. l and Z;

Fig. 8 is a sectional view on line 8-8 of Fig.

46 2, and

Fig.` 9 is a diagrammatic view illustrating a typical circuit arrangement for the control switch shown in Figs. 1 and/,2L l

The control switch' illustrated in the drawings includes a rotatable contact element I having a plurality of pairs of insulated bridging contacts 2, 3 and 4 associated therewith which cooperate with sets of stationary contacts 5, 6 and 1, respectively, carried by an insulating base 8. Said parts are mounted within an enclosing'casing (Cl. 20o- 6) comprising a frame 9 having a rear wall I0 and top and bottom.walls II and I2, and an associated U-shaped cover I3.

More specically, contact element I is provided with a plurality of molded insulating sec- 5 tions I4 which are mounted side by side upon an operating shaft I5. Said insulating sections are of like construction and as best shown in Figs. 6 and 'l each ofthe same is provided with a segmental body portion I6 having a cenl0 tr-ally disposed hub projection I1 on the base thereof which is provided with an opening for receiving shaft I5. The curved face of body portion I6 is provided with a centrally disposed peripheral groove I8 and the side faces of said l5 body portion are each similarly formed to prosaid end projections.. Also the body portion I6 20 is formed to provide a centrally disposed tongue projection 22 on one face thereofl and a centrally disposed groove 23 on the opposite face thereof.

In the embodiment illustrated there are four 25 insulating sections I4 mounted upon shaft I5, and as shown in Fig. 1 said insulating sections are clamped between a nut 25 which is threaded on s-aid shaft adjacent the lower end thereof and a star wheel 26 which is secured to said shaft 30 adjacent theupper end thereof by a pin 21. The insulatingV sections I4 are arranged so that the tongue projection 22 and groove 23 of adjacent sections engage to prevent relative rotation of said sections, and as shown inFigs. l and 8 35 the tongue 22 of the top insulating section engages within a recess 28 in star wheel 26 to lock the said insulating sections against rotation with respect to shaft I5. The hubs I1 -of insulating sections I4 are of such length that ya narrow -40 space is provided between the opposing faces of adjacent end projections I9. Also the insulating sections I4 are assembled upon shaft I5 with coil springs 30 between the opposingrfaces of said sections, said springs being held in position 45 by the opposing faces of the grooves 2l..

'Ihe three pairs of bridging contacts are removably mounted between the opposing faces-of the four insulating sections I4, and as shown in Fig. 7 each of said bridging contacts comprises 50 an elongated sheet metal stampingSI having curved contact portions 32-32 on opposite ends thereof and an intermediate shank '33 which is of reduced width to provide opposing shoulders 34--34 on opposite sides of the contact. Also 55 the shank l! is provided with a 'centrally arranged enlarged portion 35 having a struck out projection Il on one face thereof. As is apparent from Fig. 'l the shank 3l on each of the bridging contacts h insertable edgewise between the end projections Il-IS ot its insulating sections I4 into a position wherein the same clears said end projections. The contact can then be rotated about its longitudinal axis into a position wherein the shoulders 5 4 onopposite sides thereof interlock with the side faces -of the key portions 20 on the opposing faces of the associated insulating sections I4. As is apparent, the contact is then locked against both lateral and longitudinal movement with respect to its associated insulating sections I4. Also the contact is biased to move outwardly under the action ot its associated spring 30, such movement Abeing limited by engagement of its shank 3l with Y is apparent, thebridging contacts when mounted as hereinbefore described are adapted to rock upon the ends of their associated springs 30 and are also held in assembled position upon insulat' ing sections I4 by said springs.

Shaft I5 is journaled within openings in the top and bottom walls II and I2 o! bracket 9 and the upper end thereof has an operating lever 31 flxedlthereto. As hereinbefore stated, shaft I5 has a star wheel 25 secured thereto by a pin 21 and as shown in Figs. 6 and 8 the periphery of said star wheel is provided with notches 3B, I! and 40 to be engaged by a roller 4I. Roller 4I is rotatably mounted upon a lever 42 whichis pivoted as shown at 43 upon a bracket 44 ilxed to the top wall II of frame 9. Lever 42 is biased to maintain roller 4I in engagement with the periphery o! star wheel 25 by a spring 45 which is connected between the free end of said lever and a projection 46 on bracket 44. As is apparent, roller 4I cooperates with notch 39 to yieldingly hold contact element I in an intermediate position shown in Fig. 3, and said roller also cooperates with notches 38 and 40 toyieldingly hold said contact element in opposite extreme positions, one of which is illustrated in Fig. 4.

As hereinbeiore stated the pairs of bridging contacts 2, 3 and 4 cooperate with sets of stationary contacts 5, 5 and 1, respectively, carried by an insulating base 8. Insulating base 8 is formed oi.' molded insulating material and is arranged in front of contact element I. Said insulating base is rectangular in form and the upper side oi said base is provided with a pair oi supporting lugs 48-48 which are secured lto bracket 44 by screws 49 while the lower side thereof is provided with a supporting lug 50 which is secured by a screw 5I to a bracket 52 fixed to the lower wall I2 of trame 9.

The three sets oi' stationary contacts 2, 3 and 4 are horizontally alined with respect to their cooperating pairs of stationary contacts 5, 6 and 1 and each oi said sets oi stationary contacts inlcludes three contacts designated by reference characters a, b and c. Contacts b are arranged intermediate the contacts a and c and as shown in Fig. 2 corresponding contacts o! sets 2, 3 and 4 are vertically alined.

'I'he stationary contacts are of like construction,

2,1as,srs

and as shown in Fig. 5 each of the same comprises an elongated sheet metal stamping formed to provide a terminal portion 54 and a hook contact portion 55 on one end of said terminal portion. Insulating base Il is provided with individual openings 55 for receiving the several stationary contacts and as shown in Figs. 1 and 3 the rear face of said insulating base is 4formed to provide minal portion 54 of each stationary contact is provided with a tapped opening 59 for receiving a binding screw and is also provided with a wire re-4 ceiving opening 60 for receiving connections which may be arranged as shown in Fig. 2.

As shown in Figs. 1 and 2 the front face of insulating base 8 is provided with horizontally arranged ribs 6I which form horizontal wiring passages in the spaces between the sets of stationary contacts 5-6 and 6 1. Also as shown In Figs. 1 and 2 the rear face of insulating base I is provided with rearwardly projecting side ribs 62--62 and a plurality of horizontally 'arranged ribs 63 extending between said 'side ribs, the latter ribs being alined with the grooves IB in the insulating sections I4 and acting as barriers between the sets of contacts. As is apparent, the contact element I is movable in opposite directions out oi the intermediate position shown in Fig. 3 to bridge stationary contacts b with stationary contacts a. and c selectively.

Referring now to Fig.' 9 the above described control device is shown as connected to establish reverse power connections for a three phase alternating current motor M. A supply circuit for said motor is indicated by lines L1, L2 and L3, and as is apparent upon movement of contact element I4 into a position to engage stationary contacts a and b the supply lines L1, L2 and L3 are respectively connected to terminals T2, T1l and T1i of the motor. However, upon movement of Contact element I into a position to bridge stationary contacts b and c the supply lines L1, L2 and L3 are respectively connected to terminals T3, T1 and T of the motor. It is, of course, apparent that the above described control device may be connected to establish reverse power connections for motors of other types.

What I claim as new and desire to secure by Letters Patent is:

' l. In an electric switch, in combination, cooperating stationary and movable contacts, a support for said movable contacts comprising molded insulation having formed therein cavities to,support said movable contacts and to permit rocking movement thereof individually, and springs mounted within said support for normal ly holding said movable contacts in given positions and to oppose rocking movements thereof, said movable contacts being removable from said support by manipulation and said support being provided with shoulders for engaging said contacts to secure the same against dislocation by forces met with in normal operations.

2. In an electric switch, in combination, cooperating stationary and movable contacts, supporting means for said movable contacts comprising molded insulating sections arranged side by side and having formed therein complementary cavities to receive and seat portions of said movable contacts for rocking movement of theA latter individually, and springs mounted between said insulating sections to yieldingly hold said movable contacts in engagement with their cooperating seats and to oppose their rockcontacts formed to provide cavities to receive and seat the shank portions of said movable contacts for rocking movement of the latter contacts individually, and springs mounted within said support to yieldingly hold said movable contacts in their seats and to oppose their rocking movements, said movable' contacts by manipulation being readily removable from said support and said support being formed with shoulders securing said cooperating contacts against dislocation by forces met with in normal operations.

4. In combination, stationary contacts,b cooperating movable contacts each comprising a shank and contact portions at opposite extremities of said shank, a drum support for said movable contacts comprising a plurality of insulating sections mounted side by side and having cooperating faces formed to provide cavities to receive and seat the shanks of said movable contacts for rocking movement of the latter individually, and springs mounted between said sections to yieldingly hold said cooperating contacts in their seats and to oppose their rocking movements, said sections providing slots enabling said contact shanks by manipulation to be inserted in their seats and to be removed at will, and said sections being molded with shoulders securing said cooperating contacts against dislocation by forces met with in normal operation.

5. In combination, cooperating stationary and movable contacts, a molded insulating support for said movable contacts having formed therein cavities to receive and seat a pair of `said movable contacts in an opposed relation for rocking movement of the latter individually, and a cpil spring mounted in said support and interposed between said opposed contacts to yieldingly hold both in their seats and to oppose their rocking movements, said cooperating contacts being removable from said support by manipulation, and` said support being formed with shoulders securing said cooperating contacts against dislocation by forces met with innormal operation.

6. In a movable switch element, in combination, a shaft, drum sections of molded insulation mounted on said shaft, said drum sectionsj being alike and interlocking and each being molded with cavities in opposite sides, a plurality of contacts each having a portion insertable between adjacent drum sections for seating within the' cavity provided jointly by such adjacent drum sections, and springs mounted in cavities in said drum sections to bear against and to hold said contacts seated, saidv contacts having rocking movement in said cavities against the bias of said springs and said drum sections being molded with shoulders to secure said contacts against dislocation by normal forces while permitting their ready removal by manipulation.

7. Inan electric switch, the combination with an insulating base having an opening therein, of a combined contact and terminal member comprising a reflexed metal strip mounted within said opening and having a hook contact portion and a terminal portion engaging opposite faces of said base, one of the faces of said insulating base being formed to fit within said hook contact portion.

8. In a reversing switch for electric motors, in combination, a rotatable insulating support having a plurality of pairs of bridging contacts yieldingly mounted thereon, each of said pairs of bridging contacts being arranged in opposed relation on opposite sides of the axis of said support, .and said support being rotatable in opposite directions out of an intermediate off position into extreme on positions, a xed insulating base and a plurality of stationary contact sets mounted upon -said base each associated with one of said pairs of bridging contacts, each of said stationary contact sets including a contactz to be selectively engaged by its associated bridging contacts in the extreme on positions of said support and two contacts arranged on opposite sides of said former contact each to be engaged by one of its associated bridging contacts in one of the extreme on positions of said support.

9. In a reversing switch for electric motors, in combination, a rotatable insulating support having a plurality of pairs of bridging contacts yieldingly monuted thereon, each of said pairs of bridging contacts being arranged in opposed relation on opposite sides of theaxis of said support, and said support being rotatable in opposite directions out of an intermediate oi position into extreme on\positions, a Ilxed insulating base .of molded insulating material having ribs extending transversely of the paths of said bridging contacts, and a plurality of stationary contacts carried by said base to cooperate with said bridging contacts in the extreme on positions of said support, each of said stationary contacts comprising a refiexed metal stamping having a hook contact portion tting over one of the ribs on said base and a terminal portion extending through said base for securement and wiring.

10. In a reversing switch for electric motors, in combination, a rotatable insulating support having a plurality of pairs of bridging contacts yieldingly mounted thereon, each of said pairs of bridging contacts being arranged in opposed relation on opposite sides of the axis of said support and said support being rotatable in opposite directions out of an intermediate off position into extreme on positions, a fixed insulating base of molded insulating material havingone of its faces formed to provide a plurality of ribs extending at right angles to the axis of said insulating support and located between each of said pairs of bridging contacts' and a plurality oi projections extending between said ribs and a plurality of stationary contacts carried by said base to cooperate withl said bridging contacts in the extreme on positions of said support, each of said stationary contacts comprising a reilexed metal stamping having a hook contact portion tting over one of the projections on said base and a terminal portion extending Jthrough said base for securement and wiring.

y HAROLD L. MEKELBURG. 

